d2r8.txt

常用的数值算法的VB程序

Private Sub Command1_Click()
    'PROGRAM D2R8
    'DRIVER for routine POLCOF
    NP = 5
    PI = 3.141593
    Dim XA(5), YA(5), COEFF(5)
    Print
    For NFUNC = 1 To 2
        If NFUNC = 1 Then
            Print Tab(3); "Sine function from 0 to PI"
            For I = 1 To NP
                XA(I) = I * PI / NP
                YA(I) = Sin(XA(I))
            Next I
        ElseIf NFUNC = 2 Then
            Print
            Print Tab(3); "Exponential function from 0 to 1"
            For I = 1 To NP
                XA(I) = 1# * I / NP
                YA(I) = Exp(XA(I))
            Next I
        Else
            Stop
        End If
        Call POLCOF(XA(), YA(), NP, COEFF())
        Print Tab(3); "coefficients"
        For I = 1 To NP
            Print Format$(COEFF(I), "0.000000"),
        Next I
        Print Tab(5); "  x         f(x)     polynomial"
        For I = 1 To 10
            If NFUNC = 1 Then
                X = (-0.05 + I / 10#) * PI
                F = Sin(X)
            ElseIf NFUNC = 2 Then
                X = (-0.05 + I / 10#)
                F = Exp(X)
            End If
            Sum = COEFF(NP)
            For J = NP - 1 To 1 Step -1
                Sum = COEFF(J) + Sum * X
            Next J
            Print Tab(3); Format$(X, "0.#00000");
            Print Tab(15); Format$(F, "0.####00");
            Print Tab(27); Format$(Sum, "0.####00")
        Next I
        Print Tab(5); "**********************************'"
    Next NFUNC
End Sub